On nodal ground states for Schrodinger systems

In this article we characterize the least energy nodal and semi-nodal solutions to some Schrodinger system as the minimum on constrained Nehari sets of codimension 4 and 3, respectively; thus allowing to compute their Morse index and the exact number of nodal domains. Next the focus is on the symmetry properties of the sign-changing solutions. We show that, even though the domain is a ball, ground states are not radial, and produce other non-radial solutions with the given symmetry. For more information and the latex file, see https://ejde.math.txstate.edu/Volumes/2026/08/abstr.html